Types of Fluid Flow in a Pipe

Types Of Fluid Flow in a Pipe- Basic Of fluid Mechanics

Different types of fluid flow in a pipe are as : steady or unsteady, compressible or incompressible, viscous or nonviscous, and rotational or irrotational.

Types of Flows in a Pipe –

The type of flow of a fluid depends upon the manner in which the fluid particles unite and move. Though there are many types of flows, yet the following are important :

types of flow in pipe

Uniform flow:

A flow, in which the liquid particles at all sections of a pipe or channel have the same velocities, is called a uniform flow. Or, one can say velocity of the fluid particles are position invariant

This characteristic is observed in a pipe / conduit having uniform cross section.

Non-uniform flow:

A flow, in which the liquid particles at different sections of a pipe or channel have different velocities, is called a non-uniform flow. Here velocity of the fluid particles are getting varied with position.

In a non-circular cross sectional pipe / conduit this non uniformity in the flow is observed.

Streamline flow:

When a fluid particle flow along a streamline means, at any point of time at any instant if you draw a tangent it gives you the direction of the instantaneous velocity vector.

Streamline Flow

Or , simply one can define

A flow, in which each liquid particle has a definite path and the paths of individual particles do not cross each other, is called a streamline flow.

Turbulent flow:

In turbulent flow, the fluid particle does not have a definite path . Turbulent flow occurs mainly when the liquid is moving rapidly and they are also getting mixed between the layers. The speed of the fluid at a point is continuously undergoing changes in both magnitude and direction. Another way to define Turbulent flow as ;

Turbulent flow GIF

A flow, in which each liquid particle does not have a definite path and the paths of individual particles also cross each other, is called a turbulent flow.

Steady flow:

A flow, in which the velocity of the fluid particle at a particular fixed point doesn’t changes with time or one can say velocity of the fluid particle is time invariant at a particular fixed point.

Note : A steady flow may be uniform or non – uniform.

Unsteady flow:

A flow, in which the the velocity of the fluid particle at a particular fixed point is not constant, termed as an unsteady flow.

Compressible flow (variable density flow) :

A flow, in which the volume of a fluid and its density changes during the flow on the application of pressure, is called a compressible flow. All the gases are considered to have compressible flow.

Criterion for a nearly incompressible flow is a small Mach number,

where V is the flow velocity and a is the speed of sound in the fluid. For small Mach number, changes in fluid density are small everywhere in the flow field.